Description: (Adapted from the application) The Immunology and Transplantation Core is divided into two parts. The first part is to define insulitis and diabetes, as well as beta cells status. The second part is to evaluate T and B lymphocytes and antigen presenting cells. The Core will provide phenotypic analyses of mice based on The Jackson Laboratory NOD and NOR strains. Potential users will be offered analysis following backcross or speed congenic breeding of the genetically modified mice to place transgenes or knockout constructs on the background of the NOD mouse. The animals will be evaluated for insulitis, diabetes and apoptosis and if, of interest, phenotypes developing following islet transplantation under the kidney capsule.